BMW leather is certainly much better. Mom has an 06 7 series and my friends drives an 09 335i. It may not be real but it feels firmer, nicer and wears much less than ours.

 

actually his was pretty fine for the most part, but yes there electronics SUCK

 

My 07 335 has leather seats and when I returned it after 2 years it looked brand new. The BMW leather is a firmer leather and even with the sports seats it never creased or showed wear. It also has a grain texture compared to the smooth texture of the Infiniti. I would normally blame it on the Infiniti leather being soft but my wife's Lexus RX seats are super soft and they look pretty damn good after 5 years.

The leather in my 09 g37xs seems similar to that of my 04 G coupe. I can see it is going to crease pretty quickly and easily. With the sports seats I find myself pulling up from the steering wheel when getting out to try and avoid pressing my weight on the lest bolster.

I think it's a combination of the Infiniti soft leather and the very high bolsters on the sports seats.

On a side note, the sports seats are wonderful and I don't regret getting them but the right thigh bolster is a little hard against my leg. Had the same issue with my 04 G coupe.